Engine starter



June 8, 1937. J. A. CHARTER 2,082,874

ENGINE STARTER Filed Sept. 25, 1956 Patented June 8, 1937 UETED STATES 2,082,874 ENGINE STARTER of Illinois Application September 25, 1936, Serial No. 102,526

7 Claims. (01. 74-9) This invention relates generally to engine starters, and more particularly to starters adapted for use with internal combustion engines. The engine starter contemplated by the present invention is closely related to the starter shown in my co-pending application Serial No. 82,428, filed May 29, 1936.

In the starter disclosed in my above mentioned co-pending application, I have incorporated means for preventing the rebounding of a combined pinion and coiled spring unit toward the engine gear after said unit has been shifted to its out or retracted position. The present invention also contemplates preventing the rebounding of the driving pinion in a starter of the tyne wherein a tracker carried by the drive shaft unit moves within the convolutions of a coiled spring shiftable as a unit with said pinion, and also contemplates novel structural features not disclosed in my aforesaid application.

It is an object of the present invention to automatically set up increased frictional contact be-' tween the coiled spring and tracker of a starter when the pinion reaches the limit of its retracting movement to automatically establish an impositive interlock between the pinion and drive shaft unit, whereby to positively prevent the rebounding or creeping of the pinion toward the engine gear.

More specifically, my invention contemplates a structure, as set forth above, wherein variations in the spring helix will be automatically compensated for so as to positively insure the proper interlock between the pinion and drive shaft unit to prevent rebounding.

It is also an object of the present invention to provide means in association with a starter of the type set forth above, whereby the rebounding oi the pinion is not only positively precluded. but

also any subsequent creeping of the pinion toward the engine gear. In other words, the invention contemplates a single operating means which is capable of dual function, to-wit: to prevent rebounding and also to prevent creeping of the pinion.

The foregoing and numerous other objects and advantages will be more apparent from the i01 tion of the pinion being indicated by dot-anddash lines;

Figure 2 is a View similar to Figure 1, disclosing the pinion in its in or meshing position with respect to the engine gear, a portion of the pinion 5 structure being broken away to more clearly illustrate the relative positions occupied by the coacting parts;

Figure 3 is a central transverse sectional view taken substantially along the line 33 of Fig- 10 ure 1;

Figure 4 is a transverse sectional View taken along the line i4 of Figure 1, the dot-and-dash position of the lock within the pinion structure indicating the point at which frictional resist- 15 ance begins between the tracker and the coiled spring begins to increase;

Figure 5 is a transverse sectional view of the pinion extremity of a modified starter construction, the section being taken along a line similar 20 to line 33 of Figure 1; and

Figure 6 is a fragmentary perspective view of the extremity of the sleeve section which is adapted to frictionally cooperate with the lug carried by the pinion structure. 25

Referring now tothe drawing more in detail wherein like numerals have been employed to designate similar parts throughout the various figures thereof, it will be noted that one embodiment of my invention contemplates an engine 30 starter designated generally by the numeral l9, and includes arotary driving structure designated generally by the numeral l2. This rotary driving structure comprises a driving pinion proper I l and an enlarged sleeve section or 18 formed 35 integral with said pinion. A driving spring structure l8 of a multiple or double strand construction is coupled with the sleeve section [6 through the agency of hook portions 20 diametrically positioned and provided at the free extremities of the 40 spring strands. These hook portions 20 are adapted to be receivedby complementary recesses 22 formed in the sleeve sections I6. Each recess includes an axially extending portion and a circumferentially extending portion to accommodate the complementary hook 2B. The pinion and spring structure just described is mounted upon a drive shaft unit indicated generally by the numeral 24. This drive shaft unit in the present embodimentincludes a motor shaft 26 which connects with a suitable electric starting motor (not shown). The drive shaft unit 24 also includes a sleeve section 28 which is driven with the motor shaft 26 through the agency of a suitable key and keyway construction 30 (Figure 3).

A radially extending actuating member or tracker 32 is carried by the sleeve 28 and extends within the helical way 33 of the spring structure l8. A second sleeve section 34 is drivingly coupled at 35 (Figure 3) with the sleeve section 28. This sleeve section 34 provides a support for the pinion sleeve section IS. The sleeve [6 is adapted to shift longitudinally of the sleeve section 34 when the tracker 32 moves within the helical way 33. To prevent longitudinal movement of the sleeve section 28 with respect to the shaft 26, a suitable set screw 36 is provided, which is secured against loosening by means of a resilient ring 38.

It will thus be apparent that, if the starter mechanism just described occupies the position shown in Figure 1, and the drive shaft unit 24 suddenly experiences rotation in a counterclockwise direction, as viewed from the left of Figure 1, due to the activation of the starting motor (not shown), the spring structure I 8, together with the pinion structure [4, will be shifted as a unit, without rotation, to the right. This carries the pinion l4 into mesh with the engine gear 40 to be started. In other words, the tracker 32, in making one complete revolution, co-acts with the helical spring 18 so as to shift the pinion it from its out position, shown in Figure 1, to its in or meshing position, shown in Figure 2. In this meshing position, the tracker 32 engages the closed extremity 42 of the spring l8, and continued rotation of the drive shaft unit causes the pinion 14 to impart rotation to the gear 40.

As soon as the internal combustion engine (not shown) becomes self-actuated, the speed of rotation of the gear 40 exceeds the normal rotative speed of the pinion l4, thereby causing said pinion and the spring structure 18 connected therewith to experience movement to the left. As the pinion I4 and its associated elements approach the limit of its retracting movement, the frictional engagement of the tracker 32 with the side of the spring strand positioned immedi ately to the left of the tracker (Figure 1) is increased. In other words, further continued rotation of the pinion I4 is retarded due to this building-up of frictional resistance between the tracker and the spring. This building-up of frictional resistance between the tracker 32 and the spring l8 begins when a lug 44 carried by the sleeve section [6 of the pinion structure [2 frictionally engages a complementary surface 46 provided at the right extremity of the sleeve section 34. The pointat which this frictional resistance begins to build up is indicated by the dot-anddash position of the lug 34 in Figure 4. The increase in frictional resistance between the tracker 32 and the spring l8 causes a gradual deceleration of the pinion 14, or, in other words, gradually dissipates the kinetic energy stored up within. the rotating pinion and .its associated spring. As the lug 44 rotates from the dot-anddash position shown in Figure 4 toward the solid line position, the pinion experiences no further axial movement. However, due to the helix of the spring l8, continued rotation of said spring and its associated pinion relative to the tracker 32 gradually establishes a substantial increase in frictional resistance. In other words, it is not any sudden axial movement of the pinion and spring structure which causes increase in friction, but rather the gradual relative rotation between the tracker 32 and spring l8 as the lug moves from the dot-and-dash position of Figure 4 toward the solid line position which causes the increase in frictional resistance and the consequent dissipation of stored up kinetic energy.

It will be noted that a slight depression or recess 58 is provided within the surface 46. When the lug id registers with said complementary recess @8, the kinetic energy will have been dissipated, so as to arrest further rotation of the pinion ill. Immediately upon the registration of said lug and recess, the tension set up between the tracker 32 and spring it causes the lug to be suddenly seated within the recess 48. The depth of the recess 38 is not sufficient to cause any appreciable loss in frictional resistance between the track-er and spring, but is sufficient to provide a shoulder as clearly shown in Figures 1 to 3 inclusive. Should there be any slight tendency for the pinion id to rotate beyond the position shown in Figure 1, a projection or abutment 52 serves as a positive stop.

From the foregoing it will be apparent that as the lug Mi moves from the dot-and-dash position of Figure 4 to the solid line position, the gradual increase in frictional rotation between the tracker 32 and the spring 18 is sufficient to arrest rotation of the pinion Hi. I-Ience said pinion, upon reaching its out position or its position of retraction, there will be no tendency for the pinion to rebound. In other words, should the pinion and its associated structure suddenly be brought into engagement with a stop as it approaches its rearward rotary travel, the kinetic energy stored up within the pinion structure would be suddenly dissipated and said pinion would experience a marked tendency to rebound toward the engine gear 43. By providing the recess 48 and its associated shoulder 58, the pinion is secured against inadvertent movement or creeping toward the engine gear 40 as the result of vibration. Thus the shoulder 50 serves as an eifective anti-creep device. It will be apparent, therefore, that the lug and the companion surface of the sleeve 34 with which it is adapted to frictionally engage, serve the dual function of an anti-rebound and an anti-creep device. This precludes the necessity of employing an auxiliary anti-creep mechanism in addition to mechanism for preventing the rebounding of the pinion.

The design of the above described starter is such that just enough frictional resistance between the tracker and the spring is built up to effectively dissipate the kinetic energy of the pinion [4 so as to effectively prevent rebounding thereof, but not sufficient frictional resist ance to prevent free advancing movement of the pinion when the starting motor is subsequently actuated.

In Figure I have disclosed a slightly modified construction wherein the lug M is adapted to frictionally co-act with two surfaces which are designated as 45a and 55b. The surface 46a corresponds with the surface 36 previously disclosed and is provided at the right extremity of the sleeve 43. The surface @672 is provided on the right side of a collar 54 which is slidably mounted within the starter sleeve 34 and is constantly urged to the right through the agency of a suitable spring 55. A pin 5! carried by the sleeve 3 extends into a complementary slot 59 provided in the collar 53. When the lug M is out of engagement with the surfaces 46a and 46b, the collar 54 is urged to the right by the spring 56 so as to position the surface 46b slightly beyond the surface 46a. The right extremity of the sleeve 3 is provided with a suitable recess 58 to accommodate the spring 56 and the collar 54. By this construction frictional engagement of the surface 461) and the complementary inner surface of the lug 44 is insured. A recess 48a similar to the recess 48 previously described is also employed, a portion of said recess being formed in the surface 46a and the'remaining or continuing portion thereof being provided in the surface 4%.

From the foregoing it will be apparent that my invention contemplates an improved starter device for internal combustion engines and the like in which the driving pinion thereof is prevented from rebounding. The impositive frictional gripping or holding effectiveness of the lug 4d upon the right extremity of the sleeve 34 coupled with the anti-creep feature presents a very practical and desirable construction. The mechanism lends itself for manufacture by the practice of conventional machine shop methods, is durable in construction and is composed of relatively few parts.

The invention set forth herein is not limited to the specific disclosure in the drawings, but is capable of other modifications and changes without departing from the spirit and scope of the appended claims.

Having thus described my invention, what I claim as new and desire to obtain by Letters Patent is:

1. In an engine starting device, a drive shaft unit, an engine driving member on said unit adapted for both longitudinal and rotary movement, said member being adapted in one shifted position to operatively engage an engine gear to be driven, a coiled spring structure on said unit and movable with said driving member, actuating means movable with said drive shaft unit and cooperating with said coiled spring for effecting longitudinal movement of said engine riving member, an abutment section movable with said driving member, a second abutment section associated with said drive shaft unit adapted to be frictionally engaged by the first abutment section when said driving member is being retracted whereby to cause relative gradual building up of frictional resistance between said coiled spring and actuating means during the final relative rotation between said coiled spring and actuating means, and thereby gradually decelerate said engine driving member so as to prevent rebounding thereof, and means operatively associated with said. abutment sections to prevent creeping of said driving member toward the engine gear.

2. In an engine starting device, a drive shaft unit, an engine driving member on said unit adapted for both longitudinal and rotarymovement, said member being adapted in one shifted position to operatively engage an engine gear to be driven, a coiled spring structure on said unit and movable with said driving member, actuating means movable with said drive shaft unit and cooperating with said coiled spring for effecting longitudinal movement of said engine driving member, an abutment section movable with said driving member, a second abutment section associated with said drive shaft unit adapted to be .frictionally engaged by the first abutment section when said driving member is being retracted whereby to cause relative gradual building up of frictional resistance between said coiled spring and actuating means duringthe final relative rotation between said coiled spring and actuating means, and thereby gradually decelerate said engine driving member so as to prevent rebounding thereof, means operatively associated with said abutment sections to prevent creeping of said driving member toward the engine gear, and means for positively limiting the retracting rotation of the engine driving member.

'3. In an engine starting devicepa drive shaft unit, an engine driving member on said unit adapted for both longitudinal and rotary movement, said member being adapted in one shifted position to operatively engage an engine gear to be driven, a coiled spring structure on said unit and movable with said driving member, actuating means movable with said drive shaft unit and cooperating with said coiled spring for effecting longitudinal movement of said engine driving member, an abutment section movable with said driving member, a second abutment section associated with said drive shaft unit adapted to be frictionally engaged by the first abutment section when said driving member is being retracted whereby to cause relative gradual building up of frictional resistance between said coiled spring and actuating means during the final relative rotation between said coiled spring and actuating means, and thereby gradually decelerate said engine driving member so as to prevent rebounding thereof, means operatively associated with said abutment sections to prevent creeping of said driving member toward the engine gear, and means for limiting the amount of rotative frictional resistance which may be built up between said spring and actuating means.

4. In an engine starting device, a drive shaft unit, an engine driving member on said unit adapted for both longitudinal and rotary movement, said member being adapted in one shifted position to operatively engage an engine gear to be driven, a coiled spring structure on said unit and movable with said driving member, actuating means movable with said drive shaft unit and cooperating with said coiled spring for effecting longitudinal movement of said engine driving member, an abutment section movable with said driving member, a second abutment section associated with said drive shaft unit adapted to be frictionally engaged by the first abutment section when said driving member is being retracted whereby to cause relative gradual building up of frictional resistance between said coiled spring and actuating means during the final relative rotation between said coiled spring and actuating means, and thereby gradually decelerate said engine driving member so as to prevent rebounding thereon, and a shoulder extending transversely of the surface of said second abutment section and operatively associated with the first abutment section to prevent creeping of said driving member toward the engine gear.

5. In an engine starting device, a drive shaft unit, an engine driving member on said unit adapted for both longitudinal and rotary movement, said member being adapted in one shifted position to operatively engage an engine gear to be driven, a coiled spring structure on said unit and movable with said driving member, actuating means movable with said drive shaft unit and cooperating with said coiled spring for effecting longitudinal movement of said engine driving member, an abutment section movable with said driving member and having an abutment surface positioned in a plane substantially perpendicular to the axis of said driving member, a second abutment section associated with said drive shaft unit having an abutment surface lying in a plane substantially perpendicular to the plane of said driving member and adapted to be frictionally engaged by the surface of said first abutment section when said driving member is being retracted whereby to cause relative gradual building up of frictional resistance between said coiled spring and actuating means during the finalrelative rotation between said coiled spring and actuating means, and thereby gradually decelerate said engine driving member so as to prevent rebounding thereof, and means operatively associated with the abutment surfaces of said abutment sections to prevent creeping of said driving member toward the engine gear.

6. In an engine starting device, a drive shaft unit, an engine driving member on said unit adapted for both longitudinal and rotary movement, said member including an axially extending portion providing a housing and adapted in one shifted position to operatively engage an engine gear to be driven, a coiled spring structure on said unit and movable with said driving member, actuating means movable with said drive shaft unit andccooperating with said coiled spring for effecting longitudinal movement of said engine driving member, an abutment section movable with said driving member within said housing, a second abutment section associated with said drive shaft unit adapted to be frictionally engaged by the first abutment section when said driving member is being retracted whereby to cause relative gradual building up of frictional resistance betweensaidcoiledspringand actuating means during the final relative rotation between said coiled spring and actuating means, and thereby gradually decelerate said engine driving member so as to prevent rebounding thereof, and means operatively associated with said abutment sections to prevent creeping of said driving member toward the engine gear.

'7. In an engine starting device, a drive shaft unit, an engine driving member on said unit adapted for both longitudinal and rotary movement, said member including an axially extending portion providing a housing and adapted in one shifted position to operatively engage an engine gear to be driven, a coiled spring structure on said unit and movable with said driving member, actuating means movable with said drive shaft unit and cooperating with said coiled spring for effecting longitudinal movement of said engine driving member, an abutment section movable with said driving member within said housing, a second abutment section associated with said drive shaft unit adapted to extend within said housing and be frictionally engaged by the first abutment section when said driving member is being retracted whereby to cause relative gradual building up of frictional resistance between said coiled spring and actuating means during the final relative rotation between said coiled spring and actuating means, and thereby gradually decelerate said engine driving member so as to prevent rebounding thereof, and means operatively associated'with said abutment sections to prevent creeping of said driving member toward the engine gear.

JAMES A. CHARTER. 

